Signors to the siemens



` (No Model.) 0

F. B. BADT 8u 0. S. LYFORD, J1. RING ARMATURE.

No. 566,288. PatentedAug. 25, 1896.

3 5 paratively very small.

UNITED STATES ATnNT Orricn.

FRANCIS B. BADTYAND OLIVER S. LYFORD, JR., 'OF CHICAGO, ILLINOIS, AS-

SIGNORS TO THE SIEMENS t IIALSKE ELECTRIC COMPANY OF AMERICA,

OF SAME PLACE.

RING-ARMATURE.

SPECIFICATION vforming part of Letters Patent No. 566,288, dated August 25, 1896.

Application filed January l5, 1896. Serial No. 575,563. (No model.)

ro of dynamo-electric machines in which ringarmatures are employed.

A form of dynamo employing` ring-armatures that has been used to a large extent is fully illustrated in Patent No. 509,662, to C.

Hoffmann, of November 28, 1.893,` in which the armature-core is composed of iron laminee separated by layers of insulating material to reduce Foucault currents. In the form shown in this patent the commutator is mounted 2o directly upon the armature-core, the segments of the commutator constituting portions of the Winding ofthe armature, the` Winding in this case consisting of comparatively heavy strips of copper. We have 2 5 found that when dynamos of this class have been built on a large scale the permissible heat-limit is reached long before the machine can Work to the capacity Which it Would otherwise possess, since the radiating surface 3o Which must carry off the heat caused by the passage of the current through the copper conductors and by heat contributed to the laminated iron core by Foucault currents existing therein and by hysteresis becomes com- In applying our invention to the form of dynamo shown in the patent We provide in the armature-core one or more spaces which extend through the Whole depth thereof in a plane perpendicular 4o to the axis of the shaft and parallel to the plane of rotation of the armature, the number of these spaces depending largely upon the size of the machine in Which they are employed. These spaces are preferably located 45 so as to divide the armature-core into divisions having equal cross-sections. Through the core, at right angles to the radial spaces between the sections, We provide channels or lateral passages, which are preferably dis-s posed at regular intervals throughout the core.

Our invention will be more readily understood by reference to the accompanying drawings, in Which- Figure l is a sectional elevation of a dynamo-electric machine with the commutator mounted upon the ring-armature, wherein the` device of the present application is employed. Fig. 2 is a sectional view of the armature on a plane coincident with the axis of the shaft. Fig. 3 is a detail view of the armature-core.

Like letters refer to like parts throughout the several iigures.

The field-m agnets @are stationarily mounted. The armature c, surrounding the iield, is mounted upon the shaft d, by which it is rotated by means of a spider. The said armature c consists of a core c', kcomposed of iron laminae insulated from one another bylayers of paper or other suitable insulating material to prevent Foucault currents, about which are Wound the armature-coils, consisting in this case of comparatively heavy strips of copper.

XVe have shown the core divided into three sections, spaces g g intervening between the different sections and extending throughout the core in planes at right angles With the shaft d. These spaces materially assist in reducing the Foucault currents in the armature-core. At frequent intervals We provide channels t' t', transverse to the passages g g, said channels extending through the armature in plan es coincident With the axis of the shaft. In these channels c' We preferably insert short pipes 7e 7c, each of which is provided With a bell-shaped ventilator 7c k', the openings of the ventilators on one side ofv the armature extending in the direction of rotation thereof, While the ventilators on the other side of the armature extend in the opposite direction. As the armature rotates the air is taken in at one set of ventilators lo' upon one side of the armature, circulated through the passages g g and t' fr', and expelled at the ventilators 7e' upon the other side of the armature, the air on one side of the armature being forced into the ventilators, Whereas on the other side of the armature a partial vacuum is created in front of the other ventilators. By this arrangement a strong current of air is forced through the passages g g and t t of IOO the armature from one side to the other, the temperature of the armature being thereby greatly reduced.

IVe have described our invention more particularly in connection with the type of machine shown in patent No. 509,662, in which the armature rotates about internal iields; but it is obvious that our invention is applicable to other types of machine.

Ilaving described our invention, what we claim as new, and desire to secure by Letters Iatent, is-

l. In an armature for dynamo-electric machinery affording practically no passage for the exit of air-currents at its outer circumference, the combination with a laminated armature-core constructed in sections, of continuous radial spaces provided between the said sections parallel to the plane of rotation of the armature, and lateral passages provided at intervals in the body of the armature-core connecting the said radial spaces with the external air, thereby permitting a circulation of air through the said radial spaces and the lateral passages, substantially as and Jfor the purpose described.

2. In an armature for dynamo-electric machinery affording practically no passage for the exit of air-currents at its outer circumference, the combination with an armature core constructed of laminated iron plates insulated from one another and arranged in sections parallel with the plane of rotation of the armature, of continuous radial spaces provided between the said sections parallel to the plane of the armatures rotation, lateral passages provided at intervals in the body of the armature-core connecting the said radial spaces with the external air, and :means controlled by the rotation of the armature for directing the circulation oi air-currents through the lateral passages from one side oi' the armature to the other, substantially as and for the purpose described.

3. In an armature for dynamo-electric ina chinery, the combination with the sectional laminated core c o'f continuous radial spaces g between the sections thereof at right angles to the axis of the said armature, lateral passage '2" extending through the armature and connected with the radial spaces between the armature-sections, pipes 7t- 7.; connected with the lateral passage t', bell-shaped or flaring extensions 7c 7a' of the said pipes respectively turned toward and from the direction of rotation of the said armature and thereby adapted to create a circulation of air in the passages and between the sections thereof, substantially as described.

4t. In an armature for dynamo'electric machinery affording practically no passage for the exit of air-currents at its outer circumference, the combination with radial spaces or channels in the armature-core, oi' lateral passages provided at intervals in the body of the said core near the circumference oi the armature connecting the radial spaces with the external air and adapted to create a circulation of air-currents throughout the body of the armature-core, substantially and for the purpose described.

In testimony whereof we affix our signatures in the presence of two witnesses.

FRANCIS B. BADT. OLIVER S. LYFORD, .I1-z. IVitnesscs:

JoHN W. SiNcLAiR., GEORGE L. Ounce. 

